Rivet drill



Mgrch 27, 1945. H. c. 'SHOFFNER 7 2,372,398

' RIVET DRILL Filed Oct. 21, 1943 2 Sheets-Sheet l I nventar #722 v6. SHOP/WEE Patented Mar. 27, 1945 4 UNITED, STATES PATENT OFFICE 2,372,398 RIVET DRILL Harry G. Shofiner, Lawrence,tKans. Application October 21, 1943, Serial No. 507,206

1 Claim.

This invention relates to new and useful improvements in tools for removing rivets such as are used in airplane construction and more particularly to a drill attachment.

The principal object of the present invention is to provide an attachment for hand drills especially adapted for the quick removal of rivets and like securing elements.

Other objects and advantages of the invention will become apparent to the reader of the following description.

In the drawings:

Figure 1 is a side elevational view showing a hand drill equipped with the attachment.

Figure 2 is a front end elevational view of the attachment.

Figure 3 is a fragmentary section taken on the line 3--3 of Figure 2.

Figure 4 is a perspective view of the slotted sleeve.

Figure 5 is a longitudinal sectional view through the attachment.

Figure 6 is a longitudinal sectional view through the attachment taken on a plane at right angles to the section of Figure 5.

Figure '7 is a section on the line 1-4 of Figure 5.

Figure 8 is a cross section on the line 88 of Figure 5.

Figure 9 is a perspective view of the attachment with the sleeve removed.

Referring to the drawings wherein like numerals designate like parts, it can be seen that numeral 5 generally refers to a conventional drill, reference character 6 denoting the usual motor housing. The motor has a chuck 1 for receiving a bit 8 and this type of drill may employ an adapter, which is in the form of a hood and is denoted by numeral 9. This adapter is conventional and has a clamp end I serving to hold one end of the attachment which is generally referred to by numeral l l.

The attachment consists of an elongated tube l2 having a head l3, at the inner end of which is a circumferential flange l4 while its free end is beveled as at l and provided with a concaved extremity IS. A bore ll extends entirely through the tube including the head I3 and'at the intermediate portion of this structure diametrically opposite slots l8 are formed. At the inner end of the slotted portion of the element, a threaded. recess I9 is formed for the reception of a threaded element 20. On this end of the tube I2 is a sleeve 2| having a longitudinally extending slot 22 for the reception of the threaded member 20. Thus the tube |2 is slidably located within the sleeve 2|, and as is shown in the drawings, a coiled compression'spring 24 is provided on the slotted portion of the tube 2 and interposed between the flanged end of the head l3 and the adjacent end of the sleeve 2|. The sleeve 2| is clamped in the clamp portion |ll of the adapter 9 as is clearly shown in Figures 2' and 3 of the drawings.

This tube l2 fits over the head of a rivet and as the motor operates is pushed forward, the drill being centered by the tube l2 and biting into the rivet, cutting it as it progresses. The drill may be the same size as the rivet but is usually slightly smaller. When pressure is released, the spring allows the drill to recede back into the tool.

While the foregoing specification sets forth the invention in specific terms, it is to be understood that numerous changes in the shape, size and materials may be resorted to without departing from the spirit and scope of the invention as claimed hereinafter.

Having described the invention, what is claimed as new is:

An attachment for a drill comprising a tubular element for receiving the drill bit and provided with an enlarged integral front end head having a concave rivet-engaging end and a circumferentially flanged opposite end, a sleeve on said element for mounting in the drill and in which said element is slidably fitted, a slot and pin spline connection between said element and sleeve, and a coil spring circumposed on said element between said flanged opposite end and one end of said sleeve.

HARRY C. SHOFFNER. 

